Is modernisation of transport the sole answer to air pollution problems in Delhi? In view of the NGT's proposed ban on older vehicles on the streets of Delhi, Sarath Guttikunda draws attention to several problems that need to be addressed for a healthier environment in the NCR.

23 December 2014 -

On 27 March 2012 Dr. Janardhan Waghmare, posed question No.1417 in the Rajya Sabha before the Ministry of Environment and Forests (MoEF), requesting information on the prevailing status of air quality in Delhi and details of the impact of mass introduction of compressed natural gas (CNG) public and private vehicles on air quality in the capital.

In response, the (then) Minister of State for MoEF, Smt. Jayanthi Natarajan, presented a list of activities and programmes conducted by the MoEF for regulating air pollution in Indian cities; in the Annexure the minister presented the annual averages of sulfur dioxide (SO2), nitrogen dioxide (NOx) and particulate matter (PM10) pollution measured in Delhi over the period from 2000 to 2010.

The data gave rise to more questions than it answered. Between 2001 and 2005, the PM10 pollution just about remained constant, but has since risen more than 2.5 times. In 2010, PM10 concentrations averaged 260 microgram per cubic metre, which is four times the national annual standard and 13 times higher than the guidelines stipulated by the World Health Organization (WHO).

This means, whatever the benefits may have been of converting buses and auto-rickshaws to CNG were lost and overtaken by 2005, with emissions from more vehicles on the road and other sources. More recently, in November, 2014, the continuous monitoring stations operated by theDelhi Pollution Control Committee, often reported PM10 readings above 400 microgram per cubic metre.

Natarajan’s response also highlighted the contribution of the transport sector as 9-21 percent of the total PM10 pollution in Delhi. This figure comes from the MOEF’s five-year study that scientifically assessed the contribution of various sources to the ambient pollution. This study was simultaneously conducted in six cities – Delhi, Mumbai, Chennai, Kanpur, Bengaluru, and Pune. The bottom line of the assessment is that the transport sector itself (all vehicles, of all ages) accounts for at most a fifth of the pollution in Delhi.

An aerial view of Delhi. Pic: Wikimedia

For the other cities, transport sector accounts for 11-23 percent of ambient PM10 pollution in Bengaluru, 35-48 percent in Chennai, 15-17 percent in Kanpur, 8-26 percent in Mumbai, and 2-10 percent in Pune.

Hence, it calls for serious introspection: Are we asking the right questions to address the seriousness of deteriorating air quality in Delhi? Is banning older vehicles or introducing congestion tax enough to curb air pollution in the city? Most important, what else can we focus on to improve air quality in Delhi?

Banning older vehicles

In November, the National Green Tribunal (NGT) proposed to ban all vehicles older than 15 years on the roads of Delhi, and introduce congestion tax, in order to address the growing air pollution problem in the city.

It is a known fact that older vehicles are the most polluting. In 2014, a 15-year span includes vehicles introduced in 1999 or 2000, when the first set of the Bharat fuel standards (equivalent of Euro fuel standards) were introduced. In 2014, all the newer vehicles are of Bharat-IV standard and the fuel supplied at Delhi’s petrol stations is compliant with Bharat-IV fuel standards.

But without proper maintenance and retrofitting, expecting the engines from 1999 or 2000 to operate at the same fuel economy and emission levels as those introduced in 2014 defies logic. Given the stop-and-go nature of Delhi’s traffic, the wear and tear on the older engines is high and they are bound to underperform and emit more pollutants, compared to their newer counterparts.

The emissions calculations presented in the Planning Commission’s NTDPC report, highlight the role of the older vehicles, also termed “super emitters”, as the single largest contributor to on-road emissions in India. Finding a way to reduce their presence on the roads will be beneficial. The challenge is, of course, in identifying these “super emitters”, because it is not wrong to assume that the older vehicles can be maintained and retrofitted to comply with the newer standards and be clean.

In India, vehicles more than a year old are required to undergo a pollution check every six months as part of the pollution under control (PUC) programme. There are approximately 500 PUC centers in Delhi and are largely located at fuelling stations, with some along the major roads for convenience. At these centers, the tailpipe emission rates for carbon monoxide (CO) and volatile organic carbons (VOCs) are measured at engine idle speeds. These programmes are in place to check the emission levels and give a clean chit to the vehicle.

One can argue that the every vehicle that passes this test should be allowed to move on the roads. However, there is a flaw in the testing mechanism – all these tests are conducted in idling conditions, which means the tests grossly underestimate the emissions under real driving conditions – accelerating, decelerating, cruising, and idling in short intervals of time. Also, two of the key air pollutants considered for the NGT’s proposal – PM and NOx - are not measured, and if introduced as part of the default PUC protocols, could tilt the scales.

At the end of these calculations, this would be a numbers game. Every individual car could comply with the emission standards and show a clean chit. When 2 million cars and 4 million motorcycles are running on the roads together, the picture turns dirty. Therefore, we need to look for solutions where people buy vehicles, but don’t have to use them as often as they do today.

Introducing Congestion Tax

Congestion tax or congestion pricing refers to the charge levied on motorists for using a network of roads, aimed at reducing automobile (mostly car) use during peak hours, and encouraging commuters to walk, bike, or take mass transit rail/bus as an alternative, thereby easing traffic. Congestion pricing programmes were successfully implemented in Singapore, London, and Stockholm.

On average, as an outcome of congestion pricing, London experienced 20-30 percent reduction in the downtown passenger car traffic and promoted biking; Stockholm experienced an immediate reduction of at least 20 percent in daily car use; and Singapore’s average traffic speeds increased by at least 15 km an hour. In all three cities, 10-20 percent reduction in eCO2 emissions was estimated, along with health benefits of reducing air pollution.

A major reason for the success of these programmes in Singapore, London, and Stockholm was the widely accessible public transport system (road and rail) which could support the shift to a car-free environment. If congestion taxation is implemented, there will be immediate benefits in big cities like Delhi, Mumbai, and Chennai. However, the public transport system in these cities is still not at par with those in Singapore, London, and Stockholm, and hence may not prove adequate for the effective implementation of such an option.

While congestion pricing policies are difficult to replicate in the Indian context, at least for the foreseeable future, there is an important lesson. With increasing costs linked to the usage of private vehicles (fuel and other operational expenses), it is possible to achieve a shift, provided it is combined with the provision of adequate, reliable, and safe public transportation.

One possible measure in this context could be to increase parking cost. According to a study by the Centre for Science and Environment, titled “Choc-A-Block – Parking Measures to Address Mobility Crisis”, parking in most cities is currently either free or priced very low. Increased parking cost, if coupled with designated parking locations that are as far as the bus and rail stops, will make public transportation an attractive option.

Some countries have used regulatory measures to tax private vehicles differently. For instance, a Chinese national regulation enacted in September, 2008, raised taxes on big cars and reduced that on smaller ones. Car owners with engines above 4-litre capacity have to pay 40 percent tax, 15 to 25 percent for cars with engines above 3-litre capacity, and 1 to 3 percent for cars with engines below 1-litre capacity.

China also introduced a policy to limit the number of licenses issued every year, where the license plates are auctioned in the cities of Beijing, Shanghai, and Guangzhou. However, as is the case with congestion pricing, for the time being, such measures would be difficult to implement under the democratic political context of India.

Looking beyond automobile emissions

It is clear from the MoEF’s assessment that vehicle exhaust contributes to around 9-21 percent of the ambient PM10 pollution measured in Delhi, which means that at least 80 percent of the PM10 pollution is coming from non-transport sources. Even if a ban on older vehicles and introduction of congestion taxes, as proposed, are implemented, it is going to affect only a fraction of the pollution problem.

One of our assumptions is that every litre of diesel sold at the petrol station is utilised in the cars or trucks or buses. However, this is far from the truth. Frequent cuts and blackouts, and the demand for electricity in the domestic, commercial, and industrial sectors is fuelling the need for in-situ diesel generator sets.

To compensate for electricity blackouts, in areas such as Gurgaon, Noida, Faridabad, and Ghaziabad, companies and real estate developers operate massive diesel generators capable of powering small towns. Large capacity generators in hotels, hospitals, malls, markets, large institutions, apartment complexes, cinemas, telecom towers, and farm houses are all sources of emissions and contributing to the growing PM10 pollution. This is a sector which cannot be addressed by simply setting up new power plants in the region and requires a consensual dialogue between power, petroleum, energy and environment ministries.

In Delhi, construction is booming – both residential and commercial. For the purpose, bricks are available on demand, but no one asks where they are coming from. The brick manufacturing kilns are located just outside the city limits – past Ghaziabad (in the northeast), Rohtak (in the northwest), Sona, Gurgaon (in the southwest) and Noida (in the southeast). Within a 40-km radius of the city, there are at least 1000 kilns, using a mix of coal and biomass in an energy-inefficient boiler technology.

An ordinance passed in the late 90s pushed all these kilns outside the Delhi’s administrative boundary, but the emissions, under certain meteorological conditions, manage to come back into the city. While relocation of industries and clustering them proved beneficial in the past, with the growing population and expansion in city size, a more promising approach would be to introduce emerging technologies, followed by the enforcement of an inspection and maintenance program.

Re-suspended dust, including that on the roads and that from construction activities, is a major concern for most Indian cities. This is a large part of the PM10 pollution and is often difficult to quantify as it depends on the vehicle movement on the roads, road types, silt loading on roads and at construction sites, and meteorological conditions.

However, dust can be managed with measures such as wet sweeping, promoting vegetation in dry areas, paving roads, and completing the necessary road work to repair ditches and pavements that are left unattended once the concerned department (telephone, sewer, electricity, and gas) has finished its work.

During the 2010 Commonwealth Games, the Delhi transport corporation got a boost from a doubling of fleet, along with the introduction of air conditioned buses and an extension of the metro lines. The para-transit sector, 3-wheelers and taxis, also benefitted from the expansion of their fleets with more licenses. And yet, passengers complain of uncomfortable, irregular, and unsafe conditions for bus travel. The city needs at least three to four times the number of buses which are currently on the roads, to make the public transport system comfortable, regular, and safer.

Commercial heavy duty trucks are banned from entering the city limits between 6 AM and 9 PM, in order to reduce emission loads and exposure levels during day time. However, the density of these vehicles carrying raw and finished products, construction debris, sand, and bricks has increased, resulting in more emissions at night, and this pollution tends to linger even after the trucks have stopped operating at dawn. The debris and sand, which is often carried without any covers, tend to add to the silt loading on these roads.

Garbage burning is perhaps the most uncertain and the most damaging among the urban air pollution sources. The problem worsens in the winter months, when most of the garbage, along with other fuel, is used for heating purposes in many residential areas inhabited by the lower-income groups. While considerable knowledge of best practices to improve the waste collection and management exists, the problem has been in adapting these practices to specific local conditions.

Cleaning the air in our homes

The issue of indoor air pollution is also critical because of the high magnitude of population exposed to such pollution every day. According to the 2011 Census, non-LPG fuels are used in 35 percent of urban and 89 percent of rural households in India, compared to 52 percent and 94 percent respectively in 2001 with little improvement for the rural households.

A lady collects cowdung in a Bihar village, in order to shape cowdung cakes to be used for fuel. Pic: Tevaprapas Makklay/Wikimedia

Yes, but policy makers need to start looking at the problem holistically and not focus on the transport sector alone. The introduction of CNG buses was a small step, which affected a fraction of the vehicle fleet. In 2014, there are close to 8 million registered vehicles in the city and less than 50,000 account for all types of buses combined.

On the same lines, banning or retiring older vehicles and introducing congestion tax, if and when implemented, will only address a small part of the pollution problem. To sum up, therefore, cleaner air in Delhi will need a much wider net of actions, including

Identification of the key pollutants –PM2.5 is the most critical pollutant, followed by NOx and CO. The emission reduction strategies must target these pollutants first and take measures to quantify their levels in the city.

Monitoring and dissemination of data –Currently, a very limited number of monitoring stations are in operation, with limited public access to the data. For a city spanning such a large area, including the satellite cities of Gurgaon, Noida, Ghaziabad and Faridabad, the national capital region of Delhi requires at least 50 continuous monitoring stations to truly represent the pollution trends and capture all the source signals.

A shift away from ‘transport-only’ solutions – We have to recognise that pollution comes from many sources and transport is only one of them. Transport is the only source, which is visible every day, but there are other sources, which need immediate attention for short-term and long-term pollution management.

Comprehensive interventions for large and small sources – These include improving the efficiency of the manufacturing industries (especially the brick kilns); maintenance of the transmission lines to reduce power cuts and blackouts, leading to the reduced use of diesel generator sets; road maintenance to reduce dust re-suspension; bus maintenance to avoid frequent breakdowns; increase in parking fees as a disincentive for driving; and picking up garbage on time to avoid open waste burning. Once these are taken care of, any of the larger investments – either to introduce a congestion tax system, or increase the number of buses on the road, or build power plants or to construct more roads, preferably for walking and cycling – would be welcome interventions towards a cleaner Delhi.

Education of the masses – For better air quality we need to also secure greater public awareness of the problems and commitment to action at civic, commercial, and political levels. Action to tackle air pollution must be seen in the context of wider social and economic development policies. Thus, we need to see the extent to which interventions can help reduce the local challenges, for example, by providing safer and reliable public transportation systems, cleaner and efficient waste management, dust-free roads and pollution-free industries and power plants.

Sarath Guttikunda

23 Dec 2014

The author is an Adjunct Associate Professor at IIT-Mumbai in the Centre for Climate Studies and the Director of UrbanEmissions.Info, an independent research group on urban and regional air pollution.